Why do we need oxygen?

Oxygen sustains our bodies and our lives. Too little or too much, and our cells aren’t happy.

Many factors determine how much oxygen your body needs, like age, weight, conditioning, and activity levels.

The 60-100 breaths you take while reading this article will provide the oxygen you need to focus your mind and keep your body performing optimally.

At the same time, we tell you how your body utilizes oxygen at rest and during training, and how to improve your ability to intake more oxygen and use it more effectively to improve your athletic performance.

So, take a deep breath, and let’s find out: why is oxygen important?

How Your Muscles Use Oxygen

While muscle contraction is a complex process, the simplified version is that in terms of oxygen, your body uses various aerobic processes to metabolize fuels.

These processes provide you with the required energy for posture and movement.

Your skeletal muscles require oxygen to oxidize fuel (such as the carbohydrates and fats that you eat) through cellular respiration to produce the necessary energy to contract sub-maximally over long periods.

Your muscles’ ability to oxidize fuel in this way is the key adaptation of endurance training.

So how does exercise affect the muscles, and why do muscles need more oxygen during exercise?

Your Body's Oxygen Needs During Exercise

In maximal effort, short-duration sports and events such as sprints and strength training, your body uses predominantly anaerobic energy pathways to provide the required energy to your muscles.

These processes occur mainly in the absence of oxygen, and therefore quickly result in fatigue.

This is when your aerobic pathways and oxygen are necessary to sustain longer, sub-maximal efforts over longer durations.

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Endurance sports such as a marathon or triathlon can use around 10,000 kJ every two hours.

It then becomes clear that your ability to increase your body’s capacity and rate of fuel oxidation is critical to improving performance.

Intake versus Uptake: How to Improve Both to Increase Performance

Finally, it’s time to answer the burning questions you probably have: how to get more oxygen in your blood, and how to use that oxygen more efficiently to improve your muscle performance.

The two physiological processes your body will use to achieve these ends are firstly your ventilatory efficiency, also explained as the relationship between carbon dioxide production and ventilation (breathing).

Secondly, it is improving your VO2 Max, which is the maximal amount of oxygen your body can use in a given period. We want to get more oxygen in and use more of it!

So, how do you improve ventilatory capacity? One effective method that has been studied is called inspiratory muscle training.

These techniques train the intrinsic and extrinsic muscles that expand and forcefully contract your ribcage to aid the pressure exchange that occurs between your lungs and the atmosphere.

You may know that the diaphragm is the primary mover of breathing.

Other muscles, such as the intercostals and scalenes, act in ventilation, and these muscles can be trained like any other muscle to improve their strength and endurance.

Some observed improvements in inspiratory muscle training include: A higher inspiratory flow and an increased inspiratory volume and work per breath.

This means that at lower intensities, there is a reduced load on these muscles; more importantly, it means that your inspiratory muscles will gain the ability to perform faster and more powerful contractions.

This type of training can even improve your ability to perform in high altitude events where there is less oxygen in the atmosphere.

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Read more on how to training your inspiratory muscles.

Now that we have an improved ventilatory capacity to get more oxygen into our bodies, we need to improve our ability to get that oxygen into our cells to produce energy.

We must give a quick mention here to the role of the cardiovascular system in this process.

Facts about the cardiovascular system

The haemoglobin in your red blood cells is what transports oxygen from your lungs to your muscles.  
Your heart’s ability to deliver more oxygen-carrying blood to your cells, called cardiac output, is critical to improving your success in endurance exercise.

An optimal training program will develop your ability to work at a higher fractional rate of your VO2 Max, improving your performance.

Cardiac Training Can Increase Your Body's O2 intake

While genetics plays some role in your VO2 potential, improving your cardiac output through training has a powerful effect on VO2 Max.

Studies have shown that endurance-trained athletes have a cardiac work up to 20-50% greater than untrained individuals in the same demographic.

This is also reflected in the VO2 Max of elite athletes, which can be up to 60-85ml/kg/min, in comparison to an average VO2 Max for a person in their 30s of 27-40ml/kg/min.

We hope this article has given you some helpful information about how oxygen affects muscle performance, and how you can improve your athletic performance by increasing your oxygen intake and uptake.


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